Sharan Smitha, Kavitha H R, Konde Harish, Kalahasti Deepthi
Department of Prosthodontics, NSVK Sri Venkateshwara Dental College and Hospital, Bengaluru-560083, Karnataka, India.
J Contemp Dent Pract. 2012 May 1;13(3):389-93. doi: 10.5005/jp-journals-10024-1156.
To evaluate the effect of chemical disinfectant on the transverse strength of heat-polymerized acrylic resins subjected to mechanical and chemical polishing.
A total of 256 rectangular specimens (65 * 10 * 3 mm) 128 per resin (Lucitone-199 and Acralyn-H) were fabricated. One side of each specimen was not polished and the other was either mechanically (n = 96) or chemically (n = 96) polished and immersed for 10, 30 and 60 minutes in 2% alkaline glutaraldehyde. Mechanically polished (n = 32) and chemically polished (n = 32) control specimens were immersed only in distilled water. The transverse strength (N/mm(2)) was tested for failure in a universal testing machine, at a crosshead speed of 5 mm/min. Data were statistically analyzed using 2-way ANOVA and Student t-test.
chemical polishing resulted in significantly lower transverse strength values than mechanical polishing. Lucitone- 199 resin demonstrated the highest overall transverse strength for the materials tested. Heat-polymerized acrylic resins either mechanically or chemically polished, did not demonstrate significant changes in transverse strength during immersion in the disinfecting solution tested, regardless of time of immersion.
Lucitone-199 resin demonstrated the highest overall transverse strength for the materials tested and significantly stronger than Acralyn-H with either type of polishing following immersion in 2% alkaline glutaraldehyde.
There is a concern that immersion in chemical solutions often used for cleansing and disinfection of prostheses may undermine the strength and structure of denture base resins. In this study it was observed that, the transverse strength of samples of Lucitone-199 was higher than that of the samples of Acralyn-H. The chances of fracture of the denture made of Lucitone-199 are less than that of dentures made of Acralyn-H. The chemically polished dentures may be more prone to fracture than mechanically polished dentures.
评估化学消毒剂对经过机械和化学抛光的热聚合丙烯酸树脂横向强度的影响。
共制作256个矩形试件（65×10×3mm），每种树脂（Lucitone - 199和Acralyn - H）各128个。每个试件的一侧不抛光，另一侧分别进行机械抛光（n = 96）或化学抛光（n = 96），并在2%碱性戊二醛中浸泡10、30和60分钟。机械抛光（n = 32）和化学抛光（n = 32）的对照试件仅浸泡在蒸馏水中。在万能试验机上以5mm/min的十字头速度测试横向强度（N/mm²）直至破坏。数据采用双向方差分析和学生t检验进行统计学分析。
化学抛光后的横向强度值显著低于机械抛光。在测试材料中，Lucitone - 199树脂的总体横向强度最高。无论浸泡时间长短，经过机械或化学抛光的热聚合丙烯酸树脂在测试的消毒溶液中浸泡时，横向强度均未显示出显著变化。
在测试材料中，Lucitone - 199树脂的总体横向强度最高，在浸泡于2%碱性戊二醛后，无论采用何种抛光方式，其强度均显著高于Acralyn - H。
人们担心浸泡在常用于假体清洁和消毒的化学溶液中可能会破坏义齿基托树脂的强度和结构。在本研究中观察到，Lucitone - 199样品的横向强度高于Acralyn - H样品。由Lucitone - 199制成的义齿断裂的可能性小于由Acralyn - H制成的义齿。化学抛光的义齿可能比机械抛光的义齿更容易断裂。
